code: def kill(self):
      if self.proc is not None:
          print(
              f"Killing tunnel {self.local_host}:{self.local_port} <> {self.url}"
          )
          self.proc.terminate()
          self.proc = None
  
file_path: gradio/gradio/tunneling.py
imports: import atexit
  import os
  import platform
  import re
  import stat
  import subprocess
  import sys
  import time
  from pathlib import Path
  from typing import List
  import httpx
label_desc: Use image node_id 4 for calling the Tunnel obj's underlying member method code with example usage: obj.kill() without return types